JPH0226703Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a sharp pencil having a function of elastically absorbing the writing pressure to prevent lead breakage when excessive writing pressure is applied.

Conventionally, a sharp pencil equipped with such a core breakage prevention function has a core pipe that is housed in an outer cylinder so as to be slidable in the axial direction, and has a lead chuck at the tip, a chuck ring that is loosely fitted to the lead chuck, and a lead chuck that is loosely fitted to the lead chuck. a sleeve positioned between the chuck ring and the outer cylinder and fitted to the lead chuck; a spring for buffering excessive writing pressure interposed between the rear end of the sleeve and a step on the inner surface of the outer cylinder; It consists of

However, this configuration requires a sleeve, a spring for dampening excessive writing pressure, etc., requires a large number of parts, and has the drawback of complicating assembly work.

This idea was made to eliminate the above-mentioned drawbacks, and by giving the outer cylinder functions such as a sleeve and a spring for absorbing writing pressure, the number of parts was significantly reduced.
The purpose of the present invention is to obtain a sharpening pencil that simplifies assembly work and reduces costs.

An embodiment of this invention will be described below with reference to the drawings.

FIG. 1 shows a first embodiment of this invention, which includes a tip 2 fitted to the tip of an outer cylinder 1, a core pipe 3 housed in the outer cylinder 1 so as to be movable in the axial direction, The core pipe 3 has a chuck tightening tube 5 that tightens the head of the lead chuck 4 fitted near the tip thereof.

The outer cylinder 1 is made of an elastic member such as polypropylene resin or polyacetal resin, which is elastically deformable, and has a bent part 6 bent inward at its tip. This bent portion 6 abuts against the inner surface stepped portion 11 of the tip 2 and also abuts against the rear end of the chuck tightening tube 5 to restrict movement of the chuck tightening tube 5 in the backward direction. An elastic body 9 for a knot is provided between the bent portion 6 and the core pipe 3.

Further, a cushion portion 8 is formed at the tip of the outer cylinder 1. For example, as shown in FIG. 3 below, this cushion portion 8 is formed in the shape of a bellows with slits, and is formed so as to generate an elastic force in the direction of the arrow in section a in FIG. functions as a spring.

In addition to the above-mentioned shape, the cushion part 8 may have a shape as described above.
It may have any shape, such as a slit, a long hole, or a hole, as long as it generates a predetermined elastic force and functions as a spring for buffering excessive writing pressure.

According to the above configuration, the tip of the outer cylinder 1 functions not only as a sleeve but also as a spring for buffering excessive writing pressure. Therefore, when excessive writing pressure is applied to the lead during writing, the cushion portion 8 causes the lead 10 to be pushed against the outer cylinder 1.
This prevents the core from breaking. Further, separate and exclusive parts such as a sleeve and a spring for absorbing excessive writing pressure, which were conventionally required, are no longer necessary, the number of component parts can be significantly reduced, assembly work is simplified, and costs can be reduced.

The embodiment shown in FIG. 2 is an improvement on the embodiment shown in FIG. Similarly, the cushion part 7 is made of an elastic material and has a bellows-shaped cushion part 7 with a slit, as shown in FIG. are in contact. Therefore, the cushion portion 7 of the core pipe 3 functions as a spring for the lock.

According to the above configuration, the tip of the outer tube 1 has a spring function for buffering excessive writing pressure in addition to the sleeve function, while the tip of the core pipe 3 functions as a spring for the knob. Therefore, there is no need for separate dedicated parts such as a sleeve and two springs that were conventionally required, and the same effects as in the embodiment shown in FIG. 1 can be obtained.

As described above, this invention eliminates the need for separate dedicated parts such as conventional sleeves and springs, significantly reducing the number of component parts, simplifying assembly work, and reducing costs. Effects can be obtained.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of one embodiment of this invention, FIG. 2 is a longitudinal sectional view of another embodiment, and FIG. 3 is a plan view of a core pipe. 1...Outer cylinder, 2...Tip, 3...Core pipe, 4
...Lead chuck, 5...Chuck tightening pipe,
7, 8...Cushion section.

Claims (1)

[Claims for Utility Model Registration] 1. An outer cylinder 1 for gripping with a tip 2 fitted at the tip;
It is housed in this outer cylinder 1 so as to be slidable in the axial direction,
A core pipe 3 having a lead chuck 4 near its tip, a chuck clamping tube 5 for clamping the lead chuck 4, and a chuck clamping tube 5 that abuts the inner surface step 11 of the tip 2 and at the rear end of the chuck clamping tube 5. A bent part 6 is bent inward at the tip of the outer cylinder 1 so as to abut and restrict movement of the chuck fastening tube in the backward direction, and a bent part 6 is formed at the tip of the outer cylinder 1 by bending it inward. A sharpening pencil characterized in that a cushion part 8 is provided integrally with the cushion part 8 which can be elastically deformed in the axial direction. 2. The sharpening pencil according to claim 1, which is a registered utility model, characterized in that a cushion portion 7 that is elastically deformable in the axial direction is provided at the tip of the core pipe 3.